Also called 'ai Marmi' or l'obitorio (the morgue) because of its vintage marble-slab tabletops, this is Trastevere's most popular pizzeria. Think super-thin pizzas, a clattering buzz, testy waiters, street terrace and some fantastic fried starters – the supplì (Roman rice ball), baccalà (salted cod) and zucchini flowers are all heavenly.